Two years after the introduction of 10-strain pneumococcal conjugate vaccine (PCV-10) in Kenya, the percent of HIV-positive adults who carried pneumococcal bacteria declined significantly (from 43% to 28%), but did not decline in HIV-negative adults. However, the reduction in carriage of pneumococcal strains that are in PCV10 declined significantly in both HIV-positive and HIV-negative adults. This reduction was still four times higher in HI- positive vs. HIV-negative adults (2.8% vs. 0.7%), indicating that HIV positive adults continue to be at considerably higher risk of invasive pneumococcal disease than HIV-uninfected adults.
Nasopharyngeal carriage is an indicator of the risk for invasive pneumococcal disease and pneumonia
An analysis in Kenya found that, although the government will need to more than double its current vaccine budget to continue using PCV after GAVI support ends, continuing the vaccination will prevent more than 101,000 cases of invasive pneumoccocal disease and pneumonia, more than 14,000 deaths over an 11-year period, and would be cost-effective (cost per DALY of $153 by 2032), even at the full GAVI price of US $3.05 per dose.
In contrast to non-Somalis, family wealth did not significantly affect the likelihood of being fully vaccinated among Somali refugee children living in Kenya. This may point to systemic barriers to vaccination that cut across all socio-economic levels of the Somali refugee population.
Kenyan children born outside of a health facility with the aid of a traditional birth attendant were around 80% more likely to be non-vaccinated or under-vaccinated than children born in a government health facility.
Non-Somali children in Kenya in the poorest households were nearly three times as likely to be unvaccinated than children from middle-income households, while wealthier children were significantly less likely to be unvaccinated.
Somali refugee children in Kenya were nearly 60 times more likely than children of the main ethnic group in the study (Kikuyu) to not have received any childhood immunization and more than twice as likely to have not completed their vaccinations. Although Somali children made up less than 8% of the sample, they accounted for nearly half of all non-vaccinated children.
This study used data from Kenya’s Demographic and Health Survey data.
Data from the Kenya Demographic and Health Survey show that women with a primary school education were 2 to 5 times more likely to have their infants vaccinated (depending on the vaccine) and women with a secondary school education were 2.5 to 9 times more likely to have their infants vaccinated than mothers with less than a primary education or no education [after adjusting for wealth, age, religion and other variables].
Prior to the introduction of PCV, adults with HIV in a rural area of Kenya were nearly five times more likely to have pneumococcal pneumonia than non-infected adults, and the majority of cases with bacteremia (blood infection) occurred in HIV positive individuals.
The introduction of PCV-10, along with a “catch-up” campaign for 1-4 year olds, led to dramatic reductions in the rates of pneumococcal pneumonia in adults (≥18 years old) in a rural area of Kenya with high rates of both adult pneumococcal pneumonia and HIV. Over five years following the vaccine introduction, the incidence rates among adults were 47-94% lower each year than in the pre-vaccine period, with similar declines for HIV-infected and HIV-uninfected adults.
An outreach strategy in Kenya to vaccinate children against measles in hard-to-reach areas (e.g., beyond 5 km from a vaccination post) would be highly cost-effective, despite the higher cost per child to reach these children. The estimated cost per DALY averted ranged from US$122 (if 50% of these children receive the first dose and one-half of them the second dose) to US$274 (if 100% receive the first dose) — considerably less than the country’s GDP per capita of US$1,865 used as the threshold of cost-effectiveness.
